MANKATO, Minn. -- Michael Jenkins wasn't a lock to make the Minnesota Vikings' roster even after rookie Greg Childs was lost for the season.

Taking a sizeable pay cut improved Jenkins' chances.

According to NFL sources, Jenkins agreed last week to renegotiate the two years remaining on his contract and reduce his 2012 base salary from $2.5 million to $1 million. His 2013 salary also was reduced, from $2.5 million to $825,000.

Jenkins could earn back some of that money in the form of a roster bonus that increased from $750,000 under the deal he signed last July to $2.425 million. But that seems unlikely for a 30-year-old possession receiver on a rebuilding team.

It's the second time in as many seasons the Vikings have made such a deal with a veteran receiver on the bubble. After the NFL lockout ended last summer, Bernard Berrian and Greg Camarillo agreed to reduce their salaries and both made the roster.

Jenkins' situation is more complicated because concerns have been growing about his lack of explosion, which may stem from the surgery he had in late November to repair a torn meniscus in his left knee.

"I don't feel like it's an issue," Jenkins said of the knee on Tuesday, before the pay cut was revealed. "I'm just ready to go out and make plays."

He did that on Tuesday afternoon, catching four passes in team (11-on-11) drills and a couple more in a 7-on-7 red-zone period. But Jenkins' performance in Friday's exhibition opener at San Francisco was troubling, in large part because it reflected the same problems the Vikings have seen all offseason.

Dropping a back-shoulder pass that hit his hands on third-and-6 from the 49ers' 8-yard line was only the most visible issue. He moved like he had a flat tire as he has for much of camp, almost appearing to coast at a time he's in no position to do so.

The Vikings need someone to fill the void at split end during Jerome Simpson's three-game suspension to start the season. Childs, a fourth-round draft pick from Arkansas, was the top option until he tore both his patellar tendons in practice on Aug. 5.

Although Jenkins lacks the speed to be a matchup threat at the position, he has more experience and past production than the likes of Devin Aromashodu and Emmanuel Arceneaux. That threesome combined for one catch for 6 yards (by Jenkins) in six targets against the 49ers.

"It wasn't just what they didn't do, but what we may not have done at the quarterback position or at the offensive line position," coach Leslie Frazier said on Tuesday. "So, we've got some time and we hope to get our pass game going with the second group. I thought the first group did some good things in moving the football in the air, but we'll see how it progresses.

"We're counting on certain guys to make plays for us. We didn't play Percy (Harvin). Jerome will be a factor for us, but we know we won't have him for the first three games. So, Devin will get some opportunities this week. Michael Jenkins will get some opportunities. Bryan (Walters) will get some opportunities. We've still got time."

A first-round draft pick (29th overall) in 2004 by Atlanta, Jenkins got a $2 million signing bonus in addition to a 2011 base salary of $1 million on the three-year contract he signed with the Vikings last July, days after the Falcons cut him.

In 11 games (seven starts) last season before the injury, Jenkins had 38 catches for 466 yards (12.3 average) and three touchdowns.

His cap number dropped by $2 million under the new deal, leaving the Vikings about $8.6 million under their adjusted salary cap as of Tuesday evening.

The Vikings have no imminent plans to look outside the building for help in Simpson's absence, but it's always possible that could change if general manager Rick Spielman and company don't like they see.

"We're coming along good," Jenkins said of the receiver group. "We know (Simpson)'s down those first three games. We kind of say when one guy gets down, the next guy just picks up the rival and keeps shooting. We're just going to go at it."